"The only reason is that when I was a kid, the TV show Father Knows Best took place in the town of Springfield, and I was thrilled because I imagined that it was the town next to Portland, my hometown," he told the magazine.

"When I grew up, I realised it was just a fictitious name. I also figured out that Springfield was one of the most common names for a city in the US. In anticipation of the success of the show, I thought, “This will be cool; everyone will think it’s their Springfield.” And they do."

There are more than 500 episodes of The Simpsons, and the show is the longest-running sitcom on American television. But Groening has never before revealed the city on which the fictional Springfield was based - or at least named.

"I don’t want to ruin it for people, you know?" he said in the interview. "Whenever people say it’s Springfield, Ohio, or Springfield, Massachusetts, or Springfield, wherever, I always go, 'Yup, that’s right.'"

The cartoonist, who also created the long-running science fiction animation Futurama, grew up in Oregon. He named many elements of the show after his own life. His father was named Homer, for instance, and his family lived on Evergreen Terrace - just as the Simpson family do on the cartoon.

"My family lived on a long, windy road on a little dead-end street called Evergreen Terrace," he said. "Also the name of the street the Simpsons live on - and in order to visit any friends I had to walk at least a mile through the woods to get to their house."